[TenTec] Ten Tec vs. Inrad 9 MHz Filters

Jim,
I don't have my Orion yet, but all indications are the stock roofing filters
in the Orion should do the job for 99% of the situations. I have an extra
250 hertz filter from my Omni V that I am planning on adding to my Orion
when I get it. I think that would about do it for any situation.
Remember the DSP filters alone in the Orion have a shape factor of about
1.05 to 1. And the DSP has a dynamic range of 100 db. This is incredible
and I expect these filters to be the sharpest I have ever heard. My RX-340
filters have a shape factor of 1.2 to 1 and up to now, they are far and
above the sharpest I have ever heard. I can't wait to hear the Orion
filters.
Carl Moreschi N4PY
Franklinton, NC
----- Original Message -----
From: "Jim Dunbar" <jdunbar28@mchsi.com>
To: <tentec@contesting.com>
Sent: Tuesday, April 15, 2003 9:47 PM
Subject: Re: [TenTec] Ten Tec vs. Inrad 9 MHz Filters
> Hi Carl,
>
> I have a question.
>
> Do you know if most of the new Orion owners are buying the Orion with the
> optional filters installed, or are they buying the
> Orion as a stock radio without any optional filters?
>
> In other words is it essential to have the optional filters as part of the
> radio for CW operations?
>
> Thanks Ahead of Time,
>
> Jim
> K4PV
> ----- Original Message -----
> From: "Carl Moreschi" <n4py@earthlink.net>
> To: <tentec@contesting.com>
> Sent: Tuesday, April 15, 2003 3:16 PM
> Subject: Re: [TenTec] Ten Tec vs. Inrad 9 MHz Filters
>
>
> > Jim,
> >
> > There would be negligible difference by using the inrad filters in the
> > Orion. 99% of the time, the DSP filters won't even need the a narrow
> > roofing filter. The difference between the tentec and inrad filters in
> this
> > application would be almost immeasurable.
> >
> > Carl Moreschi N4PY
> > Franklinton, NC
> > ----- Original Message -----
> > From: "Jim Reid" <jimr.reid@verizon.net>
> > To: <tentec@contesting.com>
> > Sent: Tuesday, April 15, 2003 6:53 PM
> > Subject: [TenTec] Ten Tec vs. Inrad 9 MHz Filters
> >
> >
> > > Hi,
> > >
> > > I would appreciate a lead as to where I could find performance
> > > curves for the Ten Tec filters say the 217, 218, and 219 optional
> > > available for use in the Orion.
> > >
> > > I believe the TT filters are "less" steep skirted close in, but are
> > > actually more narrow further on out from the center frequency;
> > > thus actually would perform "better" in the roofing filter application
> > > in the Orion front end than the available Inrad models. Curves
> > > for the Inrad filters are found at:
> > >
> > > http://www.qth.com/inrad/tentec_menu.htm
> > >
> > > Couple of examples from the above site:
> > >
> > > Inrad 400 Hz BW CW 9Mhz filter, the #759, is down 6 dB at
> > > a BW of 455 Hz; and at 60 dB down it is 955 Hz wide;
> > >
> > > their 250 Hz filter, the #760, is down 6 dB at a BW of
> > > 315 Hz; and at 60 dB down it is 700 Hz wide.
> > >
> > > But, I have been told these actually "come back" up
> > > and have less attenuation on beyond the close in curves
> > > shown by Inrad at their site. I do not know if this is true!
> > >
> > > Why, well "only" 60 dB down is really not that large
> > > an attenuation in some ham band situations, and coming
> > > back up again could really be bad.
> > >
> > > But, I don't know how to compare to the "standard" Ten Tec
> > > filters. I had an Omni VI+ in the past equipped with the Inrad
> > > filters in all slots, replacing the TT filters. At the time I was
> > > not apprised of the possible benefit of staying with the standard
> > > Ten Tec units; that is, perhaps not as steep close in skirts,
> > > but they "stay down", hi. Frankly, I cannot say that the
> > > Inrad filters "really" made the Omni a better performer, but
> > > I did not do a direct A/B comparison, for obvious reasons:
> > > I only had one Omni, hi.
> > >
> > > Any comments, actual data per this topic would really be
> > > appreciated, should you have any or know of a source.
> > >
> > > Would like my new Orion (coming in May?, lot #2 somewhere)
> > > to have the best roofing filter performance possible, giving
> > > the narrow IF-DSP filters the greatest opportunity to provide
> > > super selectivity. BTW, have ordered the TT 1.8 kHz and
> > > 500 Hz optional roofing filters to be included with my Orion.
> > >
> > > So far, have heard of no one replacing Ten Tec filters in
> > > their Orion with the now available Inrad filters for that
> > > radio; perhaps that is sacrilege!
> > >
> > > 73, Jim KH7M
> > >
> > >
> > > _______________________________________________
> > > TenTec mailing list
> > > TenTec@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/tentec
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
>http://lists.contesting.com/mailman/listinfo/tentec